Problem with dependent implicit conversion

[odersky]

Compiler version

3.2.2

Minimized example

class Ann(x: Any) extends annotation.Annotation
object Message:
  implicit def toNoExplanation(str: String): Message @Ann(str) = ???
class Message

object report:
  def error(x: Message): Unit = ???

def test =
  report.error("a") // works
  report.error("a".stripMargin) // error

Output

10 |  report.error("a".stripMargin)
   |               ^^^^^^^^^^^^^^^
   |               Found:    String
   |               Required: Message
   |

Expectation

Should compile. The problem needs the following elements:

• the expected conversion needs to be a dependent method
• the argument needs to involve another implicit conversion in some way (in this case, the wrapper to StringLike which contains stripMargin.

[odersky]

I marked this as low-priority since it affects old style conversions only. New style conversions cannot be dependent, period.

[odersky]

@smarter suggested that it's probably the fact that the argument is not a singleton that makes a difference, since in that case we have to skolemize.

[SethTisue]

(Note that it does compile in Scala 2.13.10.)